Changes in the lungs in the early period of closed trauma of the thorax in rats

In experiments on rats it has been demonstrated that in the acute period of uninjured parts of the lungs periodic changes of protein, lipid and glucose concentrations developed. In uninjured parts of the lungs one can observe more concentration of lipids and in injured parts-more glucose. The changes of substrates, concentrations in the lungs are due to not only the changes of venous blood excess in the lungs, but are connected with metabolic changes in the cells of the injured and uninjured parts of the lungs. The metabolic changes in the lungs in the acute period of chest trauma influence the creation of such indices of gas exchange as PaCO2 and PACO2.     

More on the determinants of the fertility transition

The economic approach to fertility is an application of the economics theory of consumer behavior. It is assumed that consumers of children are utility-maximizers with stable preferences over time. Thus, changes in fertility are related to changes in household income and the "price" of children. One concern in this approach is that demographic changes are a product of changes in tastes rather than exogenous changes in economic factors such as the earning ability of women. In this paper, the effect of economic variables on the demand for children in the United States in 1950, 1960, 1970, and 1980 is examined. Support is provided for the hypothesis that the earning ability of women is an important determinant of fertility.     

Effects of anaerobic and aerobic exercises in athletes on the variation of the parameters of oxygen transport systems in different seasons of the year

Observations of the changes in the functional states of athletes of two specializations (wrestlers and skiers) carried out for four years are summarized. The effects of seasonal changes superimposed on adaptive changes caused by training are analyzed. Changes in the erythron reflecting the modulating effect of seasonal environmental changes on the state of the blood system have been found.     

The effects of the formation of Lake Kainji (Nigeria) upon the indigenous fish population

The changes in the species composition and structure of the fish population resulting from the damming of the River Niger at Kainji are illustrated and discussed. The main changes are shown to be a decline in the numbers of bottom feeding insectivores, especially the Mormyridae and an increase in the numbers of omnivores, predators and planktivores. The detailed specific changes within all the major families are examined. A brief comparison is made between the changes in the fish population following Lake Kainji's formation and the effects of the formation of other African man-made lakes     

More on the determinants of the fertility transition

Abstract

The economic approach to fertility is an application of the economics theory of consumer behavior. It is assumed that consumers of children are utility‐maximizers with stable preferences over time. Thus, changes in fertility are related to changes in household income and the “price” of children. One concern in this approach is that demographic changes are a product of changes in tastes rather than exogenous changes in economic factors such as the earning ability of women. In this paper, the effect of economic variables on the demand for children in the United States in 1950, 1960, 1970, and 1980 is examined. Support is provided for the hypothesis that the earning ability of women is an important determinant of fertility.     

The molecular organizational characteristics of the cell nucleus components at different phases of the mitotic cycle and in the resting state]

Data about the changes of the cell nucleus structure at different levels of its organization are summarized in the review. The data about the change of the DNA break number during the cycle and in resting state are presented and the role of the changes of the repair efficiency in this process is discussed. The changes of the chromatin protein spectrum, the chromatin structure at nucleosomal and supranucleosomal levels, the DNA superhelicity, topoisomerase activity, nuclear matrix composition and structure are discussed as well. The nucleus structure during the S-phase and mitosis and the cycle-related changes of the chromatin structure in lower eukaryotes are reviewed separately.     

Evaluating the statistical power of detecting changes in the abundance of seabirds at sea

There has been considerable recent concern about the plight of seabirds globally, as many species have declined substantially. In the UK there are statutory needs to monitor seabirds at sea, particularly in light of new offshore areas being designated for conservation and plans for major offshore wind farm developments. However, the extent to which at‐sea surveys are capable of detecting changes in abundance and options for improving survey protocols have received little attention. We investigate the power of detecting changes in numbers using at‐sea surveys. Using data collected as part of a visual aerial seabird survey programme that covered areas of ‘Round 2’ offshore wind farm developments in UK waters, we quantify the variability and characterize the statistical properties of count data. By generating random datasets with the same properties as real data, we estimated the power of being able to detect various declines (50, 33, 25, 15 and 10%) and assessed the effects of survey duration and frequency and of spatial scale and variability in bird numbers. The results indicate that the survey design protocols used for the UK ‘Round 2’ offshore wind farm visual aerial seabird survey programme do not provide adequate means of detecting changes in numbers, even when declines are in excess of 50% and assumptions regarding certainty are relaxed to < 80%. Extending the duration, frequency and spatial extent of surveys would increase the probability of detecting changes, but not to a desirable level (e.g. > 0.8). The primary reason why there is a low probability of being able to detect consistent directional changes is that seabird numbers fluctuate greatly at any given location. Means of explaining this fine‐scale variability are required, especially if small changes in populations are to be detected. Incorporating hydrodynamic variables into trend analysis might increase the power of detecting changes. Failure to detect changes in seabird numbers should not be taken to mean that no changes are occurring.     

Ultrastructure of cells of the lateral field of the hypothalamus of the cat after exposure to electromagnetic radiation

Under the effect of electromagnetic radiation not any specific changes are revealed in the neural system unequivocally characterizing disturbances in its structure as a result of an excess absorption of electromagnetic energy. The ultrastructural changes revealed in the lateral fields of the cat hypothalamus are suitable for a well known scheme demonstrating the course of the pathological process, where three phases are distinguished: reactive, destructive and restorative. The pathological process develops gradually. The reactive changes in neurons and synapses, observed immediately after withdrawal of the electromagnetic action. increase during the following three months and result in coarse destructive disorders and in death of some neurons and synapses. In 6 months certain signs of restoration of the structures are observed. Under the effect of electromagnetic radiation water redistribution between the structures takes place, the sympathetic terminals loosing their fluid. Thus, certain conditions are produced for sticking together the synaptic vesicles. Possibly that deficiency of Ca++ ions contributes to it.     

Effect of social isolation on the ultrastructure of the dog brain

Ultrastructural changes in the central nucleus of the amygdalar body, field CA I of the hippocampus, piriform cortex, field 17 and field 7 have been studied in dogs, bred under conditions of social isolation. The changes are more numerous in emotiogenic structures. Similar ultrastructural rearrangements are revealed in the amygdalar body, hippocampus and in both fields of the neocortex. They are: neurons with different degree of chromatolysis, reactive changes in some organelles, terminals with agglutinated vesicles, or with their reduced number, increasing amount of synapses with a short active zone. At the same time, in the piriform gyrus vacuoles, membrane-like and osmiophilic inclusions, terminals with granular vesicles of various size are found more often.     

Testosterone-dependent changes in vivo and in vitro in the structure of the renal glomeruli of the teleost Gasterosteus aculeatus L.

Summary During the reproductive period of the male stickleback, structural and functional changes of the kidney take place, both in the glomeruli and in the renal tubule cells. The structural changes in the glomeruli involve almost all glomerular components and point to a reduction of the glomerular filtration rate. The purpose of this study was to investigate whether these changes are controlled by testosterone, indirectly or directly. In vivo experiments demonstrated that exposure of immature castrates for 8 days to methyltestosterone leads to activation of mesangial cells and podocytes, to slight expansion of mesangial matrix and slight thickening of basal lamina. Observations on cultured renal tissue showed that two androgens, 11-ketotestosterone and methyl testosterone, are also able to stimulate the secretory activity of podocytes and mesangial cells in vitro. The results therefore indicate, that most glomerular changes in male sticklebacks during the reproductive season are directly effected by testosterone.     

Condition of the internal arterial and microcirculatory bed of the neck muscles of the dog after simultaneous ligation of the common carotid and vertebral arteries

In 21 mongrel dogs changes in the intraorganic arterial and microcirculatory bed of the cervical muscles have been studied after a simultaneous ligation of the common carotid and vertebral arteries. The most pronounced changes of rearrangement are observed during early periods after the operation (up to two months). The form, size of the arterial loops and direction of the blood stream change in them. On the base of the arterio-arterial anastomoses collateralies are formed, their degree of development is progressing with the increase of the postoperative time. The arteriolo-arteriolar anastomoses in small loops convert into microvascular collateralies that are of importance only during early postoperative stages. The new conditions of hemodynamics at the arteriolar level result in a dependent rearrangement in other links of the microcirculatory bed, where a number of compensatory-adaptive mechanisms are revealed. After the magistral by-pass ways are completely formed, the changes observed disappear and the microcirculatory network acquires the features specific for intact animals.     

Changes in the cell population of the thymus-dependent area of the regional lymph nodes following skin flap grafting

In the paracortical zone of the regional lymph node changes in the cell population density of small and middle lymphocytes, immunoblasts, immature and mature plasma cells are taken into consideration. The observations are carried out for 954 h after transplantation. As demonstrates the analysis of the process segmentation, certain stages of the changes are revealed with duration of 150-160 h; that corresponds to circadian (circaseptan) range of biological rhythms. The duration of the first stage makes about a half of the circaseptan period. In quantitative changes of every cell type a slow trend and a periodical component are present. It is possible to suppose that during the first 3-4 days mobilization of cell resources takes place, further up to 13-16 days active reactions occur, directed to exfoliation of allogenic tissue components, and then after the exfoliation of the graft the amount of the cells becomes stable, however, rhythmical fluctuations are preserved. The reaction of the cell composition in the paracortical zone of the lymph nodes is in concord with the dynamics of changes in the cell population and in the transplant itself.     

Possible Involvement of Humoral Regulation in the Effects of Elevated Cerebral 4-Aminobutyric Acid Levels on the Polyamine Metabolism in Brain

Abstract: It has been reported in several recent studies that the manipulation of cerebral 4-aminobutyric acid (GABA) level results in unexpected changes in the cerebral polyamine metabolism in vivo . The mechanisms behind these interactions have remained unknown. The present results show that the changes in polyamine metabolism are not limited to the brain, but are observable also in the liver, which served as a peripheral reference tissue. Different types of responses in the activities of the poiyamine-synthesizing enzymes, ornithine decarboxylase and adenosylmethionine decarboxylase, were observed after increasing the cerebral GABA concentration of mice with varying doses of two GABA transaminase inhibitors, gabaculine and ethanolamine- O- sulphate. The time course of the significant changes in the enzyme activities showed significant correlation between the brain and liver. The possibility of direct effects of the drugs on liver was excluded by injecting them intracerebroventricularly, and by performing control experiments with equal doses given peripherally. It is concluded that the observed changes in the polyamine metabolism of liver are produced through centrally mediated humoral regulation, and that the corresponding changes in the brain are obviously due to the same factor or factors, since they are significantly correlated to the changes in liver.     

Ultrastructural changes of the posterior silk gland cells in the early larval instars of the silkworm, Bombyx mori

The posterior silk gland cells in the first three larval instars show characteristic changes during growth that are essentially similar to those undergone in the fourth larval instar. In the feeding stage, when the cells grow rapidly, vesico-tubular rough endoplasmic reticulum and a number of Golgi vacuoles occur in the cytoplasm and the glandular lumen is filled with fibrous materials, probably fibroin. In the moulting cycle when the cells stop growing, a series of degenerative changes occur such as the appearance of autophagosomes, autolysosomes, and large vacuoles. Fibrous materials disappear from the glandular lumen. These cyclic changes are discussed in relation to hormonal changes. Intercellular junctions and the tracheal system of the silk gland are described.     

Functional and morphological basis for the nature of the microcirculatory bed reactions of the bulbar conjunctiva in experimental occlusion of the cranial mesenteric artery

A complex analysis on changes occurring in conjunctival microcirculation and a number of indices of hemodynamics, hemorheology and metabolism at different time of experimental occlusion in the cranial mesenteric artery has demonstrated certain objective and many-sided correlations that prove a systemic character of biomicroscopical changes in the conjunctiva. The degree of changes in the conjunctival microcirculation depends on duration of occlusion. After a 3 hours' occlusion revascularization is accompanied by reversible general microcirculatory disorders that are registered in bulboconjunctiva. In a 6 and 12 hours' occlusion revascularization is characterized by increasing general changes in microcirculation.     

Morphofunctional features of the secretory cells of the adenohypophysis and adrenal glands of the rat during aging

Karyometric and electron microscopic investigation has been performed in the adenohypophyseal secretory cells, in the cortex and medulla of the adrenal glands in mature (6 months) and ageing (25-26 months) white male rats. The diameter of the corticotropic cell nuclei of the adenohypophysis significantly increases with age. In the secretory cells of the adrenal cortex and medulla no important changes in their parameters are revealed. With age destructive changes of the ultrastructures are manifested variously in different types of the secretory cells in the endocrinic glands studied. In the corticotropic, somatotropic, thyreotropic cells of the adenohypophysis, in spongiocytes of the adrenal cortex, compensatory ultrastructural rearrangements develop; they are aimed to preserve functional activity of the cells mentioned. No age changes are revealed in ultrastructure of chromaffin cells of the adrenal medulla.     

Comparative ultrastructural characteristics of the anterior lobe of the hypophysis, thyroid and gonads in mammals during aging

Ultrastructural changes in certain types of adenocytes of old rats, guinea pigs, rabbits and dogs are characterized by specific peculiarities. However, the direction of these changes mainly coincides. The somatotropic function of rats, guinea pigs and rabbits is suppressed, lactotrophic and corticotrophic cells being activated with aging. The phenomenon of the overstrain of gonadotrophic and thyrotrophic cells is registered. Dystrophic changes in the peripheral glands are observed.     

Hemodynamic mechanisms of the pulmonary artery pressure and blood flow changes following vasoactive depressor drugs injection

The character and values of changes of the pulmonary hemodynamics and venous return following acetylcholine, histamine and isoproterenol intravenous injection were studied in acute experiments on the anesthetized cats. After depressor drugs injection the character and values of changes of pulmonary artery pressure and flow were different. In 67% cases the pulmonary artery pressure was decreased, and in 33%--it was elevated, meanwhile the pulmonary artery flow was decreased in 48% cases and it was increased in 52%, i.e., in the equal number of observations. Thus, following depressor drugs intravenous injection, hemodynamic mechanisms of the changes of pulmonary artery pressure and flow are different. The character and values of changes of the pulmonary artery pressure are correlated with the changes of pulmonary vascular resistance and are not dependent with the left atrial pressure shifts. The changes of the pulmonary artery blood flow are caused by the changes of the venous return and are not correlated with the changes of the right and left atrial pressure.     

13C-NMR studies of the effects of the carcinogen acetylaminofluorene on the conformation of dinucleoside monophosphate

13C-NMR spectra are obtained in aqueous solution of dinucleoside monophosphates (ApG and GpA) and of their adducts formed by the addition of the carcinogen acetylaminofluorene (AAF) to the C8 position of the guanine. The base and sugar carbons of all dimers and adducts are assigned. The task of assigning base and carbohydrate resonances was accomplished using a series of reference compounds. Significant changes in many of the carbon resonances of the adducts are observed suggesting three general conformational changes, namely: (1) chemical shift changes are noted in base carbon atom resonances as a function of temperature and adduct formation which are indicative of stacking effects; (2) large upfield shifts of the furanose C2' resonance of the guanosine-adduct indicate a shift to higher populations of the syn conformation. Other shifts of carbohydrate resonances are indicative of a change in conformation of the carbohydrate itself. (3) Large temperature effects on linewidth of several fluorine and furanose resonances indicate interconversion of various conformers in the dimer adduct.     

Studies on monotreme proteins. VI. Amino acid sequence of the beta-chain of haemoglobin from the platypus, Ornithorhynchus anatinus.

The amino acid sequence of the 146 residues of the beta-chain of the major haemoglobin from the platypus has been determined. The soluble peptides derived from the chain by tryptic digestion were isolated by paper ionophoresis and chromatography. The amino acid sequences were determined by the dansyl-Edman procedure or by further digestion with other enzymes. The tryptic peptides were aligned by homology with other beta-globins. There were 14 changes in sequence compared with echidna beta-chain. The number of changes in sequence compared with human beta-chain is 34 which is less than the 39 changes between human and platypus alpha-chains. Generally there are more changes between beta-chains; there are only three other examples reported where there are more changes between alpha-chains than beta-chains, these are of echidna, rabbit and dog globins. By comparison with the 'contact sites' in horse haemoglobin there is one change in beta-haem contacts, three changes in beta1-alpha1 contacts and no changes in beta2-alpha1 contacts. The date of divergence of the monotremes from the other mammals was estimated at 132 +/- 33 million years, based on the number of amino acid differences between species and allowing for multiple mutations during the evolutionary period. This estimate differs widely from the estimate given by similar treatment of the alpha-chain sequences and the significance of this discrepancy to the validity of the method is discussed.